Body gyrating mechanism



March 6, 1934. w WETTLAUFER 1,949,703

BODY GYRAT ING MECHANI SM Filed July 16, 1932 s Sheets-Sheei 1 INVENTORY 3 49 4M A TTORNEYS March 1934- w. 1.. WETTLAUFER BODY GYRAT I NGMECHANISM Filed July 16, 1932 3 Sheets-Sheet 2 BY M ATTORNEYS March 6,1934- w. L. WETTLAUFER v BODY GYRATING MECHANISM Filed July 16, 1932 3Sheets-Sheet 3 INVENTOR M7 121/725 [dd/! M M pwm A TTORNE Y5 PatentedMar. 6, 1934 20 Claims.

This invention relates to body syrating mechanisms such as are employed,for example, in connection with vibrating screens. More particularly theinvention is concerned with mechanisms of the type which utilizeanti-friction bearings to maintain at a low value friction losses whichwould otherwise occur owing to the weight of the body and thecentrifugal forces set up by its movement.

The principal object of the invention is to provide a novel arrangementof the bearings and associated parts, whereby to provide a simple andeconomical construction.

A further object is to provide a construction wherein the bearings areso arranged that their 2 may be determined solely by and in accordancewith the load that they are to carr A still further object is to providefor the reinforcement of the drive shaft, whereby arrangement of thebearings in a common plane in order to avoid objectionable bending orflexing of the drive shaft is not essential.

A still further object is to provide for facility in lubricating thebearings.

The invention is illustrated in the accompanying drawings, in which:

Figure 1 is a side elevation of a vibrating screen in which features ofthe invention are incorporated.

Figure la is an enlarged fragmentary section taken along line lat-1a ofFigure 1.

Figure 2 is an enlarged sectional view taken along line 2-2 of Figure 1.

Figure 3 is a section taken along line 3-3 of Fig. 2.

Figure 4 is a section taken along line 4-4 of Fig. 2.

Figure 5 is a sectional view similar to Figure 2 of another embodimentof the invention.

Figure 6 is asection taken along line 66 of Fig. 5.

Figure 7 is a section taken along line 'i-7 of Fig. 5.

The features by which the invention is characterized render it ofparticular advantage as the actuating mechanism of screens of theso-called vibrating type and it is, therefore, illustrated and describedin connection with such a screen. It is to be understood, however, thatthe invention is not limited to such use, such illustration being by wayof example only.

The screen which is illustrated in connection with the gyratingmechanism is of conventional construction. It comprises a body 10between the side walls 11 of which the usual screen decks are arrangedand a. supporting frame 12 upon which the body is mounted for vibratorymovement. The frame is rectangular in form and consists of side members13 and end members 14, the body being mounted between the former andabove 80 the latter. Each side member includes a pair of beams 15 ofchannel-shape cross-section (Figures 1a and 2) which are secured back toback against spacing blocks 16. The frame 12 is suspended by cables 17at the angle necessary to insure fiow of 66 the material across thescreen decks in the desired direction, the cables being secured toconvenient overhead structure and being connected to the frame by clamps18 which engage over the flanges 19 of the beams.

The gyrating mechanism which is indicated generally at 20 (Figure 1) isavailed of, in the embodiment illustrated, to actuate the body 10 in themanner disclosed in my co-pending application, Serial No. 180,016, filedMarch 31, 1927, i. e. to gyrate it in circular paths at a relativelyhigh speed thereby to facilitate rapid screening of the materialintroduced into the body. To this end the gyrating mechanism is, asdisclosed in the said application, employed in connection with springs21 (Figure let) one of which is arranged at each corner of the screenbody. The said springs carry a substantial part of the load of the bodyand serve the further purpose of maintaining the latter in correctscreening position while permitting its positive actuation in the mannerdescribed by the gyrating mechanism. The springs 21, as illustrated, fitwithin housings 22, the latter being suitably secured to the side walls11 of the screen body. The side members 13 of the frame carry plates 23which extend laterally beneath the housings 22 to co-operate with thesprings. The latter are under compression and hence act against theplate 23 to urge their respective corners of the screen body upwardly.

The gyrating mechanism 20, as illustrated, ineludes a fixed shaft 24(Figure 2) which extends through the screen body substantiallycoincident with the center of gravity thereof and which is supported byits reduced ends 25 upon the side members 13. For this purpose thelatter carry blocks 26 of bearing-like construction which are suitablysecured upon the side members and in which the reduced ends of the shaft24 are mounted. The mechanism also includes a tubular shaft 27 which isco-axial with the shaft 24 and a tubular housing 28 which fits over theformer. The housing is formed or provided at each end with a bearingchamber 29, the said chamber 110 being defined by an annular wall 29awhich extends through an opening 30 provided for this purpose in a sidewall 11 of the screen body. The chamber providing portion of the housing28 is formed with an annular flange 31 by which the housing is securedto the wall 11 with suitable nut and bolt fastenings 32. The housing 28,therefore, is secured to the side walls of the screen body while theshaft 24 is secured to the supporting frame 12. The tubular shaft 2'7,on the other hand, extends beyond the annular walls 29a of the bearinghousing and carries on the extension a drive wheel 33, the latter beingfixed to the shaft by a key 34. The wheel 33 is adapted to be connectedto an electric motor 35 (Figure 1) by suitable belt means 36, the saidmotor being suitably supported from the frame 12.

The drive shaft 27 is supported for concentric rotative movement aboutthe shaft 24 by roller bearings 3'7, the inner ring 38 of which fitsover the reduced end of the shaft against a shoulder 39 and the outerring 3911 of which fits snugly within the end of the shaft 27. Thebearings 3'7 which will hereinafter, for convenience, be referred to asthe main bearings are adapted to carry that part of the dead loadrepresented by the screen body and contents which is not carried by thesprings 21.

The inner ring 40 of a set of roller bearings 41, is keyed upon theshaft 27 by the key 34, the outer ring 42 of the said set fitting snuglywithin the bearing chamber 29 in substantially the same plane as thatoccupied by the main bearings 37. The inner ring 40 is formed to providean eccentric enlargement or cam upon the shaft 27. In other words theperipheral surface of the ring 40 is eccentric to the axis of the driveshaft 2'7. The outer ring 42 is concentric with the periphery of theinner ring 40 and hence rotary movement of the drive shaft 2'7 istranslated into a gyratory movement which is transmitted through thebearings 41 to the housing 28, and hence the screen body. The bearings41 which will hereinafter, for convenience, be referred to as theeccentric bearings are adapted to carry the load which is created as aresult of the screen body gyrating about the axis of the main bearing.This load varies directly as the eccentricity of the ring 40 and as thesquare of the angular speed of the shaft 27.

The eccentric bearings, therefore, must be designed to carry the maximumof a variable load range. On the other hand the load on the mainbearings is substantially always the same, the load being equal to thetotal load minus that part thereof which is carried by the springs 21.The maximum load which is carried by the eccentric bearings isconsiderably greater than the load which is carried by the mainbearings. The latter are, therefore, in the interests of economypreferably correspondingly smaller than the former. It will be apparentthat the transmission of power to the screen body in the mannerdescribed has the advantage that when the main and eccentric bearingsare arranged in substantially the same plane in order to eliminatebending stresses, each of the bearings may be designed solely withreference to the load that it is to carry without regard to the size ofthe other. The cost of production, therefore, is maintained at aminimum. A further advantage obtained is that the shaft 24 provides arigid mounting for the main bearings and hence the necessity ofself-aligning bearings for this purpose is avoided.

The drive wheel 33 is availed of to counteract the centrifugal forcesdeveloped by the screen body gyrating about the main bearing axis. Tothis end the rim thereof is formed with an annular slot or guideway 43of dovetail cross-section. A counterbalance 44 is secured to the Wheelby a tongue 45 of dovetail cross-section, the said tongue fitting withinthe guideway 43. The counterbalance consists of two sections 46 and 4'7which are held against relative movement in the guideway by a set screw48 carried by the section 47. The reduced end 49 of the set screwregisters with a suitable opening formed in the section 46. By looseningthe screw 48 slightly the section may be adjusted as a unit to the pointdesired while by tightening the said screw the sections may be locked insuch position. By adjusting the set screw so that the end 49 thereof iscompletely withdrawn from the hole in the section 46, the two sectionsmay be detached from the wheel by first slipping them apart in theguideway. The sections may be assembled when the set screw is in thesame position by slipping them together in the guideway and thentightening it to wedge the tongue 45 firmly against the walls of theguideway. It will be apparent from the foregoing that the counterbalance44 may be adjusted to eliminate the centrifugal forces developed by thescreen body gyrating around the main bearing axis. In other words, thecentrifugal forces pass through the eccentric bearings to the balancewheel and do not pass to the main bearings. In this connection it isunderstood, of course, that the drive shaft 2'7 is journaied at the endopposite from that shown in a similar bearing assembly and that abalance wheel similar to the wheel 33 is preferably employed therewith.

A suitable lubricant may be supplied to the bearings through a fitting50 carried by the reduced end of the shaft 24. The fitting communicatesthrough a duct 51 with the interior of the drive shaft in the vicinityof openings 52 which are formed therein. A portion of the lubricantwhich is discharged from the duct 51 may, therefore, pass by way of saidopenings through a passageway 53 to the eccentric bearings while anotherportion may fiow along the drive shaft through a passageway 54 to themain bearings. Owing to centrifugal force the lubricant which isdischarged into the drive shaft 27 is, during operation of themechanism, forced under pressure to the eccentric bearings, while a partthereof which does not pass through the openings 52 is forced axially ofthe shaft toward the passageway 54. Lubrication of the bearings is thusfacilitated. It will be apparent that the bearings may be lubricatedeither while the mechanism is running or while it is at rest. A furtheradvantage which is obtained is that either oil or grease may be employedas the lubricating medium.

Means is provided for preventing escape of the lubricant from thebearing chamber. For this purpose a seal is employed in connection witheach of the main and eccentric bearings. The seal employed in connectionwith the former includes a stationary part 55 which is carried by thereduced end of the shaft 24 and an inter-fitting part 55a carried by thedrive shaft 27. The seal employed in connection with the eccentricbearings includes a ring 56 which is screwed in the open end of the wall29a of the bearing housing and which is formed with a plurality ofannular ribs 57 which fit in companion recesses 58 formed in the face ofthe wheel 33. The annular wall 29a of the tubular housing 28 moveseccentrically with respect to the axis of the wheel 33. The recesses 58,therefore, are formed eccentric with respect to the axis of the wheel 33to a corresponding degree.

From the foregoing it will be apparent that the construction describedis simple and economical and that owing to the ease with which thebearings may be lubricated wearing of the latter may be maintained at aminimum.

In the embodiment illustrated in Figure 5 the side members 59 of thesupporting frame are in the form of beams of standard construction andthe fixed shaft 60 of the mechanism passes through the side walls 11a ofthe screen body and is secured at its ends to said beams by suitablebrackets 61. The mechanism, similarly to that described in the firstembodiment, includes a tubular drive shaft 62 which fits over the shaft60 and a tubular housing 63. The latter carries a collar 54 which issuitably secured over the end of the said housing and which is formedwith an annular axially extending rib 65 and a laterally extendingshoulder 66. The rib fits in an opening 67 formed in the side wall 11aof the screen body while the shoulder abuts the inner face of that partof the wall which defines the opening. A cap piece 68 is formed with abody portion 69 which fits within the open end of the collar 64 and aflange '70 which abuts the outer face of that part of the side wall 11awhich defines the opening 67. Securement of the housing to the side wall11a of the screen body is effected by the collar 64 and cap piece 68 andto this end each is formed with co-operating laterally extending flanges'71 between which the side wall is secured by suitable nut and boltfastenings '72.

The drive shaft 62 has a cam sleeve '73 fitted over and suitably securedto each of its ends, the inner walls 7% of the sleeves being concentricwith the shaft 60. The drive shaft is supported for rotative movementupon the shaft 60 by ball bearings '75, the inner ring '76 of which isfitted over the reduced end 77 of the shaft 60 and the outer ring '78 ofwhich is fitted within the end of the cam sleeve '73. The bearings '75are adapted to carry that part of the dead load of the screen .bodywhich is not carried by the springs which are arranged at the fourcorners of the screen body and which function similarly to the springsdescribed in connection with the embodiment first described. Power istransmitted to the drive shaft 62 through the agency of a drive wheel'79 which is fitted over the cam sleeve '73 and keyed thereto by a key80, the said drive wheel being secured upon the sleeve by a nut 73a.Inasmuch as the wheel '79 is mounted upon the sleeve '73, the hub 81 ofthe wheel is formed correspondingly eccen- Ipiece 68. The bearings 82are adapted to transmit the centrifugal forces developed by the gyratingmovement of the screen body to the counterbalancing means. Theycorrespond, therefore, to and function similarly to the eccentriclbearings described in the first embodiment. As

distinguishing from the said first embodiment, however, the drive shaft60 carries a counterbalance 85, the diameter of the tubular housing 63being large enough to accommodate it while permitting the housing togyrate about the drive shaft 62 in the manner described. Thecounterbalance 85 is adapted to eliminate a substantial part of thecentrifugal forces set up by the movement of the screen body. It ispreferred, however, that the drive wheel 79 carry an auxiliarycounterbalance 86 which in construction is similar to that described inconnection with the first embodiment, the said counterbalance beingadjustable to co-operate with the counterbalance to counteract thecentrifugal forces set up by 85 the screen body.

The eccentric bearings 82 are encased within a lubricating chamber 87which is provided by the cap piece 68 and a second cap piece 88, thelatter fitting within the collar 64 and being secured in such positionby the body portion 69 of the cap piece 68. Lubricant is introduced intothe lubricating chamber 8'7 through a fitting 89 which communicates withthe chamber through a duct 90 formed in the reduced end '77 of the shaft60 and one or more openings 91 which extend through the drive shaft 62and cam sleeve '73. A portion of the lubricant discharged from the duct90 is forced along the shaft 60 to the main bearings '75 and lubricatesthe latter. In order to seal the lubricating chamber 87 the cap piece 68is preferably formed with annular recesses 92 which co-operate withannular ribs 93 formed on the wheel 79, the said ribs having a runningfit in the recesses. Lubricant from the main bearing '75 is preventedfrom escaping by a suitable seal which, as illustrated, includes astationary member 94 carried by the reduced end '77 of the shaft 60 anda rotatable member 95 which is secured in the end of the cam sleeve 73by the nut 73a, the said members being formed respectively with aco-operating recess and rib which function in the conventional manner.It will be noted that in this embodiment the main and eccentric bearingsdo not occupy the same vertical plane. They are, however, relativelyclose together and the shaft 60 and housing 63 are capable ofcounteracting to a. high degree the tendency of the drive shaft to bendunder the influence of the centrifugal forces developed by the movingscreen body. In other respects the construction disclosed in Figure 5 issubstantially the same as that described in Figure 1.

I claim as my invention:

1. Mechanism for actuating a body in the manner described including asupport, a member carried by said support and upon which said body ismounted, a hollow shaft fitting over said member and journaled thereon,means for rotating said shaft, eccentric means carried by said shaft andmeans carried by said body and journaled on said eccentric means,whereby upon rotation of said shaft a gyrating movement is imparted tosaid body.

2. Mechanism for actuating a body in the man- 135 ner describedincluding a support, a member carried by said support and upon whichsaid body is mounted, a hollow shaft fitting over said member, ananti-friction bearing by which said shaft is supported upon said member,means for rotat- 14o ing said shaft, eccentric means carried by saidshaft and anti-friction bearing means co-operating with said eccentricmeans and said body, whereby upon rotation of said shaft a gyratingmovement is imparted to said body.

3. Mechanism for actuating a body in the manner described including asupport, a shaft carried by said support and upon which said body ismounted, a hollow shaft fitting over said first mentioned shaft, ananti-friction bearing by which said hollow shaft is supported upon saidfirst mentioned shaft, means for rotating said hollow shaft, eccentricmeans carried by said hollow shaft and anti-friction bearing meanscooperating with said eccentric means and said body, whereby uponrotation of said hollow shaft a gyrating movement is imparted to saidbody.

4. Mechanism for actuating a body in the manner described including asupport, a member carried by said support and upon which said body ismounted, a hollow shaft fitting over said member, an anti-frictionbearing by which said hollow shaft is supported upon said member, meansfor rotating said hollow shaft, eccentric means carried by said hollowshaft and antifriction bearing means co-operating with said eccentricmeans and said body, whereby upon rotation of said hollow shaft agyrating movement is imparted to said body, said anti-friction bearingand bearing means being located in a common plane.

5. Mechanism for actuating a body in the man ner described including asupport, a shaft carried by said support and upon which said body ismounted, a hollow shaft fitting over said first mentioned shaft, ananti-friction bearing by which said hollow shaft is supported upon saidfirst mentioned shaft, said bearing being designed to carry the loadrepresented by the dead weight of said body, means for rotating saidhollow shaft, eccentric means carried by said hollow shaft, andanti-friction bearing means co-operating with said eccentric means andsaid body, whereby upon rotation of said hollow shaft a gyratingmovement is imparted to said body, said anti-friction bearing meansbeing designed to carry the load represented by the centrifugal forcesset up by the movement of said body.

6. Mechanism for actuating a body in the manner described including asupport, a shaft carried by said support and upon which said body ismounted, a hollow shaft fitting over said first mentioned shaft, ananti-friction bearing by which said hollow shaft is supported upon saidfirst mentioned shaft, said bearing being adapted to transmit the deadweight of the body to said first mentioned shaft, means for rotatingsaid hollow shaft, eccentric means carried by said hollow shaft,anti-friction bearing means cooperating with said eccentric means andsaid body, whereby upon rotation of said hollow shaft a gyratingmovement is imparted to said body, and means for counterbalancing thecentrifugal forces set up by said body, said anti-friction bearing meansbeing adapted to carry the load represented by such forces.

7. Mechanism for actuating a body in the manner described including asupport, a shaft carried by said support and upon which said body ismounted, a hollow shaft fitting over said first mentioned shaft, ananti-friction bearing by which said hollow shaft is supported upon saidfirst mentioned shaft, said bearing being designed to carry the loadrepresented by the dead weight of said body, means for rotating saidhollow shaft, eccentric means carried by said hollow shaft, andanti-friction bearings means co-operating with said eccentric means andsaid body, whereby upon rotation of said hollow shaft a gyratingmovement is imparted to said body, said antifriction bearing means beingdesigned to carry the load represented by the centrifugal forces set upby the movement of said body and both of said bearing means beinglocated in a common plane.

8. Mechanism for actuating a body in the manner described including asupport, a member carried by said support and upon which said body ismounted, a hollow shaft fitting over said member, an anti-frictionbearing by which said shaft is supported upon said member, means forrotating said hollow shaft, eccentric means carried by said shaft, atubular housing fitting over said member and shaft and being secured tosaid body and anti-friction bearing means co-operating with saideccentric means and said housing, whereby upon rotation of said shaft agyrating movement is imparted to said body.

9. Mechanism for actuating a body in the manner described including asupport, a member carried by said support and upon which said body ismounted, a hollow shaft fitting over said member, an anti-frictionbearing by which said shaft is supported upon said member, said bearingbeing designed to carry the load represented by the dead weight of saidbody, means'for rotating said hollow shaft, eccentric means carried bysaid shaft, a tubular housing fitting over said member and shaft andbeing secured to said body and antifriction bearing means co-operatingwith said eccentric means and said housing, whereby upon rotation ofsaid shaft a gyrating movement is imparted to said body, saidanti-friction bearing means being designed to carry the load representedby the centrifugal forces set up by the movement of the said body.

10. Mechanism for actuating a body in the manner described including asupport, a member carried by said support and upon which said body ismounted, a hollow shaft fitting over said member, an anti-frictionbearing by which said shaft is supported upon said member, a wheelcarried by said. hollow shaft which is adapted for connection to powerto rotate said shaft, eccentric means carried by said shaft,anti-friction bearing means co-operating with said eccentric means andsaid body, whereby upon rotation of said shaft a gyrating movement isimparted to said body and an adjustable weight carried by said wheel forvarying the counterbalancing effect of the latter.

11. Mechanism for actuating a body in the manner described including asupport, a member carried by said support and upon which said body ismounted, a hollow shaft fitting over said member, an anti-frictionbearing by which said shaft is supported upon said member, a wheelcarried by said hollow shaft which is adapted for connection to power torotate said shaft, eccentric means carried by said shaft, a tubularhousing fitting over said member and said shaft and being secured tosaid body, anti-friction bearing means co-operating with said eccentricmeans and said housing, whereby upon rotation of said shaft a gyratingmovement is imparted to said body and an adjustable weight carried bysaid wheel for varying the counterbalancing effect of the latter.

l2. Mechanism for actuating a body in the manner described including asupport, a member carried by said support and upon which said body ismounted, a hollow shaft fitting over said member, an anti-frictionbearing by which said shaft is supported upon said member, a wheelcarried by said shaft which is adapted for connection to power to rotatesaid shaft, eccentric means carried by said shaft, anti-friction bearingmeans co-operating with said eccentric means and said body, whereby uponrotation of said shaft a gyrating movement is imparted to said body anda weight secured to said shaft for counteracting the centrifugal forcesset up by the movement of said body.

13. Mechanism for actuating a body in the manner described including asupport, a member carried by said support and upon which said body ismounted, a hollow shaft fitting over said member, an anti-frictionbearing by which said shaft is supported upon said member, a wheelcarried by said shaft which is adapted for connection to power to rotatesaid shaft, eccentric means carried by said shaft, anti-friction bearingmeans cooperating with said eccentric means and said body, whereby uponrotation of said shaft a gyrating movement is imparted to said body, aweight secured to said shaft for counteracting the centrifugal forcesset up by the movement of said body and auxiliary adjustable weightcarried by said wheel for co-operating with said first mentioned weight.

14. Mechanism for ctuating a body in the manner described including asupport, a member carried by said support and upon which said body ismounted, a hollow shaft fitting over said member, anti-friction bearingby which said sha t is supported upon said member, a wheel ca ied bysaid shaft which is adapted for connection to power to rotate saidshaft, eccentric means carried by said shaft, a tubular housing fittingover said member and shaft and being secured to said body, anti-frictionbearing means co-operating with said eccentric means and said housing,whereby upon rotation of said shaft a gyrating movement is imparted tosaid body, a weight secured to said shaft within said housing forcounteracting the centrifugal forces set up by the movement of said bodyand an adjustable auxiliary weight carried by said wheel forco-opcrating with said first mentioned weight.

15. Means for actuating a body in the manner described including asupport, a member carried by said support and upon which said body ismounted, a hollow shaft fitting over said member, an anti-frictionbearing by which said shaft is supported upon said member, means forretating said shaft, eccentric means carried by said shaft,anti-friction bearing means co-operating with said eccentric means andsaid body, whereby upon rotation of shaft 2. gyrating movement impartedto said body and means, including a duct which is formed in said member,for providing a passage through which lubricant may be forced to saidanti-friction bearing and bearing means.

16. Mechanism for vibrating a screen including a support, a shaftcarried by said support and upon which said screen is mounted, a hollowshaft fitting over said first mentioned shaft, antifriction bearings bywhich said hollow shaft is supported upon said first mentioned shaft,means for rotating said hollow shaft, bearing housings secured to theopposite sides of said screen, eccentric means carried by said hollowshaft and anti-friction bearing means co-operating with said eccentricmeans said bearing housings, whereby upon rotation of said hollow shafta gyrating movement is imparted to said screen.

1'7. Mechanism for vibrating a screen including a support, a shaftcarried by said support and upon which said screen is mounted, a hollowshaft tting over said first mentioned shaft, anti-friction bearings bywhich said hollow shaft is supported upon said first mentioned shaft,means for rotating said hollow shaft, a tubular housing fitting overboth of said shafts and secured at its opposite ends to opposite sidesof said screen, the ends of said housing being formed to provide bearingchambers, eccentric means carried by said hollow shaft and anti-frictionbearing means in said chambers for co-operating with said eccentricmeans, whereby upon rotation of said hollow shaft a gyrating movement isimparted to said screen.

18. Mechanism for vibrating a screen including a support, a shaftcarried by said support and upon which said screen is mounted, a hollowshaft fitting over said first mentioned shaft, anti-friction bearings bywhich said hollow shaft is supported upon said first mentioned shaft,said bearings being designed to carry the load representative of thedead weight of said body, means for rotating said hollow shaft, atubular housing fitting over both of said shafts and secured at itsopposite ends to opposite sides of said screen, the ends of said housingbeing formed to provide bearing chambers, eccentric means carried bysaid hollow shaft and co-operating with said eccentric means, wherebyupon rotation of said hollow shaft a gyrating movement is imparted tosaid screen, said bearing means in each housing being located in acommon plane.

19. Mechanism for vibrating a screen including a support, a membercarried by said support and upon which said body is mounted, a hollowshaft fitting over said member, anti-friction bearings by which saidshaft is supported upon said member, means for rotating said shaft, atubular housing fitting over said member and shaft and secured at itsopposite ends to opposite sides of said screen, the ends of said housingbeing formed to provide bearing chambers, eccentric means carried bysaid shaft, anti-friction bearing means carried by said shaft andlocated in said chambers, whereby upon rotating of said shaft a gyratingmovement is imparted to said screen and means, including a duct which isformed in said member, for providing a passage through which lubricantmay be forced into said bearing chambers.

20. Mechanism for actuating a body in the manner described including asupport, a member carried by said support and upon which said body ismounted, a hollow shaft fitting over said member, anti-friction bearingsby which said shaft is supported upon said member, eccentric meanscarried by said shaft, a wheel for rotating said shaft, said wheel beingmounted upon said eccentric means, the hub of said wheel being eccentricrelative to its periphery to a degree such that the latter is concentricwith the axis of said mem her and antifriction bearing meansco-operating with said eccentric means and said body, whereby uponrotation of said shaft a gyrating movement is imparted to said body.

WILLIAM L. WETTLAUFER.

